Operation Manual

Filters and Spoofing
26 NetWAYS/ISDN – 3 Remote Access with NetWAYS/ISDN
Filters and spoofing mechanisms in data communication
The following spoofing mechanisms are available to reply to
LAN overhead packets, depending on the network protocol
used (IPX or IP):
Watchdog spoofing
NetWare servers send out watchdog packets at regular
intervals to verify that the clients logged in on the server
are still active. These watchdog packets are intercepted
in the LAN by the AVM Access Server. The Access Server
simulates an acknowledgment by the remote computer,
without activating the connection to it.
SPX spoofing
Many LAN applications use IPX/SPX. SPX servers and
clients exchange “keep-alive” packets at regular inter-
vals to verify that a given application is still active. SPX
packets must be acknowledged at both ends in order
for the logical SPX connection to be maintained.
If SPX spoofing is activated, SPX packets are acknowl-
edged locally by the remote access server in the LAN,
and not forwarded over ISDN to the remote client. Keep-
alive packets generated by an application on the client
ISDN
Remote computer
with NetWAYS/ISDN
User data:
Files, etc.
Network data packets:
NetBIOS, SNMP and NCP
AVM Access Server
NetWAYS/ISDN
Filter and
spoofing
mechanisms
User data: E-mail, etc.
Network data packets:
Watchdog, SPX, ARP,
NetBIOS, SNMP and NCP
User data:
Files, etc.
User data:
Files, etc.
User data:
E-mail, etc.
Remote Access Server
Filter and spoofing
mechanisms
User data:
E-mail, etc.
User data:
Files, etc.
User data:
E-mail, etc.
Local Network (LAN)
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